NEET Test 6

The tendency of a system to be in their state against unfavorable factor is called Stability, the ability of regaining its original shape or position after being deformed is called Resilience. Hence, it has low stability and high resilience.

Amongst the following, Zea maize will be selected for production of bioethanol. Bioethanol is a clean fuel that can be used as a fuel additive or substitute for fuel etc. Bioethanol can be produced from crops like sugarcane, maize, potato etc.

Agrobacterium tumefaciens is used in transfer of foreign DNA or transgenes into crop plants. The technique of transferring the transgene is known as transformation and is either done by using Agrobacterium or direct transfer is done. Agrobacterium technique is used commonly as it does not require regeneration from explant tissues.

Bt (Bacillus thuringeinsis) toxin is an inactive prototoxin that converts to active form in the insect’s gut. When an insect eats Bt toxin, the toxin binds with receptors in gut, the crystals thereby causing the gut wall to break down and allowing spores and gut bacteria to enter the insect’s body and thus killing it.

Polyethylene Glycol (PEG) is a chemical method used for vector-less gene transfer. The protoplast of the plant is treated with solution having PEG, DNA and various ions. The chemicals and various ions bring changes in the plasma membrane thus allowing the DNA to penetrate and move into the cytoplasm by endocytosis.

Transgenic plants are obtained by introducing foreign DNA into a cell and then regenerating plant from that particular cell. Transgenic plants are defined as plants with foreign DNA incorporated into their cell. These plants are also known as genetically modified organisms (GMO’s).

Active growing regions of plants like the shoot and root apex are free from viruses therefore these regions are used in production of plants free from viruses using meristem culture. Explant from the meristem of either root apex or shoot apex are obtained & cultured on a medium with more cytokinin and less auxin to raise virus-free plants.

Continuous addition of sugars in fed batch fermentation is done to purify enzymes. Fed batch fermentation implies continuous addition of fresh growth medium during fermentation and no removal of growth medium until the process ends. This strategy increases yield more than 1000 percent.

Amongst the following, Zea maize will be selected for production of bioethanol. Bioethanol is a clean fuel that can be used as a fuel additive or substitute for fuel etc. Bioethanol can be produced from crops like sugarcane, maize, potato etc.

deficiency of vitamin A causes night blindness. Golden rice is the transgenic rice which is rich in vitamin A and is also contains good quantity of beta-carotene. 
Flavr savr tomato is genetically modified crop which remains fresh for much longer time than tbe normal tomatoes due to depressing the fruit softeninh enzyme polygalacturonase. 
Bt soyabean is also a genetically modified crop in which bacillus thuriengenesis bacteria is merged which prevent the crop from the larvae.

Monocarboxylic acids have a number of functional isomers. These are- 
(1) Hydroxyl carbonyl compounds i.e., aldehydes and ketones 
(2) Esters 
(3) hydroxyoxiranes

The reactivity order of carboxylic acids toward the esterification reaction is- 

R₃-C-COOH< R₂-CH-COOH< R-CH₂-COOH< CH₃COOH< HCOOH 

It is due to the steric hinderance of –CH₃ which creates the instability and decreases the reactivity order of carboxylic acid.

Solution :

Esterification is a relatively slow process at room temperature and does not proceed to completion. Thus, concentrated sulfuric acid is used. It plays two roles during the reaction- 
(i) To speed up the reaction. 
(ii) To acts as a dehydrating agent, forcing the equilibrium to the right resulting in the greater yield of ester.

Esters are the organic compounds having fruity smell. The aroma of an ester is produced when an alcohol combines with a carboxylic group (carbon bonded with oxygen atoms).

Carboxylic acids lose CO₂ to form hydrocarbon on heating sodium or potassium salts of carboxylic acid with sodalime. 

CH₃COONa + NaOH + CaO → CH₄ + Na₂CO₃